Effect of annealing treatments on photoluminescence and charge storage mechanism in silicon-rich SiN x :H films

Abstract

In this study, a wide range of a-SiNx:H films with an excess of silicon (20 to 50%) were prepared with an electron-cyclotron resonance plasma-enhanced chemical vapor deposition system under the flows of NH3 and SiH4. The silicon-rich a-SiNx:H films (SRSN) were sandwiched between a bottom thermal SiO2 and a top Si3N4 layer, and subsequently annealed within the temperature range of 500-1100°C in N2 to study the effect of annealing temperature on light-emitting and charge storage properties. A strong visible photoluminescence (PL) at room temperature has been observed for the as-deposited SRSN films as well as for films annealed up to 1100°C. The possible origins of the PL are briefly discussed. The authors have succeeded in the formation of amorphous Si quantum dots with an average size of about 3 to 3.6 nm by varying excess amount of Si and annealing temperature. Electrical properties have been investigated on Al/Si3N4/SRSN/SiO2/Si structures by capacitance-voltage and conductance-voltage analysis techniques. A significant memory window of 4.45 V was obtained at a low operating voltage of ± 8 V for the sample containing 25% excess silicon and annealed at 1000°C, indicating its utility in low-power memory devices.

Correlation between charge transport and electroluminescence properties of Si-rich oxide/nitride/oxide-based light emitting capacitors

“…[1][2][3][4][5][6][7][8][9][10] Silicon-rich silicon nitride (SRSN) and silicon-rich silicon oxide (SRSO) materials have mostly been considered due to their good emission properties (under optical and electrical excitation) and compatibility with the mainstream complementary metal oxide semiconductor (CMOS) technology. [1][2][3][4][5][6][7][8] Much effort has been dedicated to improve the electroluminescence (EL) intensity as well as the efficiency of the light-emitting devices. [1][2][3][4] Published works span from those centering the attention on the material optimization in terms of the different fabrication processes, 6,7 to those that mostly focus on the electrical and EL properties.…”

“…[1][2][3][4][5][6][7][8] Much effort has been dedicated to improve the electroluminescence (EL) intensity as well as the efficiency of the light-emitting devices. [1][2][3][4] Published works span from those centering the attention on the material optimization in terms of the different fabrication processes, 6,7 to those that mostly focus on the electrical and EL properties. [8][9][10] Efficient light-emitting devices have already been demonstrated using either SRSN or SRSO films.…”

Effect of the stoichiometry of Si-rich silicon nitride thin films on their photoluminescence and structural properties

“…Wide bandgap SiN x materials demonstrate a high density of deep level traps [3,4], allowed strong trapping of electrons and holes, achieving intense luminescence in the blue-green spectral range to be realized [5,6]. This offers the possibility for the development of multicolor Si-based A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT 2 light-emitting devices.…”

“…PL spectra of the samples grown with different R values and measured at 300 K.Curves 1-4 correspond to R=1.0 (1), 0.83 (2), 0.71 (3) and 0.63(4). All spectra were normalized on the maximal PL intensity.…”

Luminescent Devices Based on Silicon-Rich Dielectric Materials

“…Therefore, defects are created rather than Si-nps, after thermal annealing. Moreover, due to the low difusivity of silicon atoms in Si 3 N 4 , a high Si content (>52 at.%) is needed to form Si-nps [59,60]. Because of the low Si content present in the SRN ilms from this work (<46 at.%), as shown above in the XPS results, these ilms can be explained as a sub-stoichiometric nitride with structural defects, as reported in the study of Cabañas-Tay et al [34].…”